In systems where digital data is encoded by an encoder, transmitted in packets of digital data, and decoded by a receiver, the encoder may receive data that includes digital samples of analog signals. Video transcoding (or decoding) can be used to transcode video streams to an appropriate video format and bit rate. A Digital Media Adaptor (DMA) may then decode the stream and render it on a television.
Before transcoding or decoding the data can begin, however, some systems may first require that a complete picture be located in a buffer. To locate and determine whether a complete picture is present in the buffer, the system may parse the stream looking specific start codes. Due to the variety of digital data formats and sizes of pictures, the system may need to scan the entire current buffer when receiving one or more packets of data. As new data is received in the buffer, the previously scanned data is often scanned a second time, along with the newly received data, while searching for the aforementioned start codes. Thus, conventional picture locating algorithms require either receiving a large amount of data to parse for a complete picture or repeated searches of the buffer whenever receiving new data. Such methodologies and devices may be inefficient and lessen the performance of the decoding/transcoding system.